Taken on a foggy day at the last floor of the sears tower. I admire the construction workers that can work at those heights.
The 2 small lines on the left are antennas from another skyscraper, check the version on flickr so you can view better details on a larger version, really worth it.
Just submitted this pic for Photo of the Year at Photoblog Awards, you can vote here, votes are more than welcomed.
PS: happy bday Pao & Oche.